The use of metals in restorative dentistry is well known. Metals, per se, or preferably alloys comprising metals used in restorative dentistry have to possess certain properties to be suitable for their intended use. In general, alloys which have been found most suitable are gold alloys or gold alloys containing platinum. These alloys have been most used because they possess an extremely high chemical stability against discoloration and dissolution in the mouth, as well as possessing preferred mechanical properties such as high extensibility, excellent workability, and high wear resistance. However, while these gold alloys have been found to be most suitable, the increasingly high price of gold is making their use economically prohibitive, and it would be desirable to provide alloys possessing the desirable properties of the presently used gold alloys but being much less expensive.
The use of alloys containing metals other than gold, silver or the metals of the platinum family in the restorative dental field is known. U.S. Pat. No. 4,094,671 describes an alloy containing 48-52% copper and 47-51% zinc as the major constituents along with a minor amount (0.1 to 1.0%) zirconium as well as other metals. U.S. Pat. No. 4,255,190 describes an alloy containing cobalt and chromium as the major constituents. This alloy is particularly suitable for adhering to low-fusing procelain.